You have to feel sorry for the wave of French youngsters born just too late to have been part of the Paris student riots of 1968, because they really missed out on a party. Something in the Air, the new film by Olivier Assayas, who was only 13 during that fateful year of striking, is a wry tribute to the idealistic kids forced to follow in some mighty big footsteps.

We open in 1971 with a bang, and a baton to the head, as a group of naïve revolutionaries wearing crash helmets and tie-dye t-shirts square up to Paris's riot gear-clad police force. These high school anarchists, finely played by mop-haired teenage greenhorns, are out of their depth, but you have to admire their spirit. They feverishly read leftist magazines with firebrand names like J'Accused and Rogue, and publish their own left-wing rag that's so radical the Trotskyists that run the printing press have to shut them down. When they fail miserably to take back the streets, they take on their high school, festooning its façade in a riot of iconoclastic posters and revolutionary slogans.

Our proxy into this world of youth in revolt, and essentially a stand-in for Assayas, is the adorably pretentious Gilles (Clément Métayer). Early on he's dumped by his girlfriend, Laure (Carole Combes), who's more cosmopolitan than him, reads Beat poetry, and looks as if she's stepped off the cover of Sgt. Pepper's Lonely Hearts Club Band. Her excuse for the breakup is that she's spending the summer in Ibiza, but we suspect the real reason Gilles has been kicked to the curb is that he's plucked up the courage to show her his abstract paintings—amateurish Jackson Pollock knockoffs that Laure witheringly critiques post coitus. Now a free agent, Gilles sets off on a trip to Italy for a summer of discovery with fellow artist Alain (Félix Armand) and new girlfriend Christine (Lola Creton, a knockout in Goodbye First Love, by Assayas's partner Mia Hansen-Løve).

The trio travels with a filmmaking collective that specializes in left-wing propaganda. When one of the humorless documentarians, a diehard Maoist, chides Gilles for reading The Chairman's New Clothes and refuses him access to the group's equipment to make a short film ("We don't make fiction," he sneers), it becomes clear that Assayas is muddying the waters. An innate tension exists between artistic expression and political collectivism, a fact Gilles will wistfully come to terms with by the end of the film. What's so charming about Something in the Air, and what sets it apart from countless sentimentality-choked coming-of-age movies, is its canny balance of nostalgia with hindsight. Assayas clearly adores his blissfully quixotic protagonists, not least for their political and artistic ardor, but he doesn't over-romanticize them either. They wear their foolishness on their sleeves as well as their hearts.

The film, which loses some of its propulsion, if none of its smarts, when these characters hit the road, ends on a beautifully melancholic grace note. When Gilles returns home from Italy, he trades life in the precocious world of fine art for a gig as the runner on an exploitation movie featuring Nazis, Amazon women, and prehistoric beasts. Another anarchist swapping radicalism for the life of the petite bourgeoisie—or so you'd think. As Gilles shuffles off-set to fetch more tea, Assayas's camera soars, with Kevin Ayers's "Decadence" blaring on the soundtrack and smoke from a papier-mâché sea monster billowing across the soundstage, and we see our hero's silhouette 20-feet tall as he strides across the back projection. His radical friends would scoff at such a spectacle, but this is cinema as rhapsody and Gilles is at its heart.